Zoos are indeed a good example. Although the environments are made as close as possible to the natural habitats, penguins are often kept in open-air enclosures in temperate or even tropical climates. And there are two critical differences in even the most carefully constructed zoo: the absence of any predators, and the absence of any prey. So why don't the animals quickly/purposefully/nonrandomly cease exhibiting developmentally costly traits which give them an advantage against predators or prey who aren't present?
Label: Sarcastic